飼料用稲を基軸とする耕畜連携システムの計量分析モデル

コントラクター介在型システムの場合

抄録

Whole rice plants can be fed to cattle as whole crop silage (RWCS). By an “integrated farming system of arable and livestock” is meant the following: (1) Arable farmers supply RWCS to livestock farmers, where feed rice is harvested and processed by the local agricultural contractor; (2) Livestock farmers supply cattle waste compost to arable farmers, where compost is applied to feed rice cropping paddies by the local agricultural contractor. The farming system is expected to supply multilateral benefits such as improving domestic feed self-sufficiency, recycling cattle waste, and conserving paddy fields, So the government has promoted production and utilization of feed rice by subsidies. This study intends to construct an econometric model of the farming system and examine how the impact of external factors affect feed rice production. The econometric model was specified as follows: (1) Livestock farmers are assumed to minimize cost subject to livestock product output constraints, where constant elasticity substitution production function is applied to capture the imperfect substitution between RWCS and other coarse feed; (2) Arable farmers are assumed to choose feed rice output levels to maximize profit; (3) Local agricultural contractor is assumed to keep the balance of revenue and expenditure. The experimental simulation was implemented with this model, which quantified the impact of subsidy policy reform, improvement of feed rice productivity through introduction of direct planting technology, and price climb of other coarse feed.